RESUMO
The emergence of retinal monoamine neurons was explored in embryonic and larval goldfish (Carassius auratus) by means of a histofluorescence technique. The high-affinity uptake capacity of dopamine (DA) and indoleamine-accumulating (IA) neurons for exogenously applied DA and 5,6-dihydroxytryptamine began to occur simultaneously on the hatching day (stage 25/26). Endogenous DA neurons were first detected on the third postnatal day (stage 26/27). The appearance of DA and IA neurons was found to begin in the central part and to extend to the peripheral part of individual retinas. The first DA and IA neurons to be detected were situated in the inner nuclear layer and migrated proximally to the innermost level of the inner nuclear layer 5-7 days after hatching. The developmental process of monoamine neurons observed represents an aspect of cellular differentiation and maturation in the goldfish retina.
Assuntos
5,6-Di-Hidroxitriptamina/metabolismo , Cyprinidae/citologia , Dopamina/metabolismo , Carpa Dourada/citologia , Retina/crescimento & desenvolvimento , Animais , Diferenciação Celular , Histocitoquímica , Microscopia de Fluorescência , Neurônios/fisiologia , Retina/metabolismoRESUMO
A considerable number of mitochondria (10-20 percent) are closely connected with the granular endoplasmic reticulum at the early stages of oogenesis in loach. The number of ribosomes on sections of the endoplasmic reticulum turned toward the mitochondria is considerably greater than on other sectors of the membranes. The work discusses the role played by contacts between the mitochondria and the granular endoplasmic reticulum in the biogenesis of oocyte mitochondria at the early stages of oogenesis.
